Earlier quoted context omitted.
I love bitcoin and cryptocurrency as potential solutions to problems with gov-controlled currencies (I've used crypto to buy drugs, for example). But I'm still confused why people refer to purchasing currency as an "investment." Obviously the rates are going up now, but doesn't everyone expect them to just come back down? I don't convert my USD to Yen and call it an "investment."
You would call it an investment, if the USD-YEN prices are so volatile and give you 1000X profit in 6 months. Again, this all goes back to whether Bitcoin is a store of value or a medium of exchange. By now it's very clear, it can't be medium of exchange.
You can say what you want about the philosophy of that - the lightning network will add yet another group of people who collectively have an outsized control over the network. But if the scaling issues get addressed I don't see any reason why it couldn't work as a currency. And it looks like they are being (slowly) addressed.